Rangefinding

Binoculars with mil ticks

• https://en.wikipedia.org/wiki/Milliradian#Units_for_target_size_and_range
• https://www.reddit.com/r/ArmaReforger/comments/1jfuen2/us_m22_binocular_range_finding/
• https://www.schaper.net/binoculars/steiner/m22/
• Range Estimation with ACOG and M22 Binocular

1 mil is 1 meter in width or height at 1000 meters.

If an object fills 10 mils in the binos, and is known to be 1 m high, the object
is 100 m away.

If an object fills 10 mils in the binos, and is known to be 10 meters wide, the
object is 1000 meters away.

6400 mils in a circle. (NATO)

18 mils in 1 degree.

The field manual entry

• The long vertical lines on the axis represent 5 milliradians
• The half-sized lines indicate 2.5 milliradians

On the example UAZ-469, with a length of approximately 4 meters, one can
estimate its distance.

As it is 20 milliradians long we can make the calculation

(4 x 1000) \ 20 = 200. The vehicle then is 200 meters away.

Math

Either way works out the same:

• Distance = (Target Size / Mil Reading) * 1000
• Distance = (Target Size * 1000) / mils

A person is 1.8 m tall.

The tick marks in binoculars are 5 mil apart.

(1.8 * 1000) / 10 = 180 m

5 = 360

Common measurements

Person

• 1.8 m tall

mils:

• 10 = 180 m
• 7.5 = 240 m
• 5 = 360
• 2.5 = 720 m

BTR

• 8 m long
• 3 m wide
• 2.5 m high
• 1.1 m tire

UAZ

• 4 m long
• 1.8 m wide
• 2 m high

LAV-25

• 6.4 m long
• 2.5 m wide
• 2.7 m high

BRDM-2

• 5.75 m long
• 2.4 m wide
• 2.3 m high

EOTECH range estimation

The EOTECH donut is a 60 MOA ring surrounding a 1 MOA center dot.

The donut provides several aiming points:

• Center dot: out to 300 m ish the center dot is usually accurate enough
• Bottom tick mark can be used to engage targets out to 600 m

We can then estimate range based on the ratio of target to donut

100 meters

A man-sized target will fill the entire 68 MOA circle from top to bottom.

Aim point center dot.

200 meters

The target will reach from the center dot to the bottom of the donut.

Aim point center dot.

300 meters

The target will cover approximately two-thirds of the distance from the
center dot to the bottom of the donut.

Aim point center dot.

400 meters

The target will fill about one-fourth of the distance from the center
dot to the bottom of the donut.

Aim point halfway point between center dot and bottom of donut.

500 + meters

The target is tiny.

Aim point is tick mark at bottom of donut.